Temperature controller system for controlling temperature of an object and an apparatus including same

ABSTRACT

A temperature controller includes a bath for containing a refrigerant. One cooling line has one end connected to the bath and the other end branching off into a plurality of diverged lines. The first diverged line is connected to an edge portion of an object. The second diverged line is connected to a middle portion of the object. The third diverged line is connected to a central portion of the object. A plurality of valves for controlling flux of the refrigerant are mounted on inlets of the plurality of diverged lines, respectively. A plurality of temperature sensors for detecting temperatures of the refrigerant are mounted on outlets of the plurality of diverged lines, respectively. A controller controls opening angles of the plurality of valves in accordance with the detected temperatures of the refrigerant.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority under 35 USC § 119 to Korean Patent Application No. 2003-94360, filed on Dec. 22, 2003, the contents of which are herein incorporated by reference in its entirety for all purposes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a temperature controller system for controlling temperature of an object, and an apparatus including the temperature controller system. More particularly, the present invention relates to a temperature controller system for controlling the temperature of an area in which a wafer is disposed, and an etching apparatus for uniformly etching a surface of the wafer using the temperature controller system.

2. Description of the Related Arts

Generally, a semiconductor device may be manufactured by stacking a semiconductor material, a conductive material and a non-conducting material on a semiconductor substrate and then by patterning the stacked layers. A process for forming a pattern may include a photolithography process for forming a photoresist pattern which is produced by exposing and developing a photosensitive photoresist film formed on an underlying layer on the semiconductor substrate using a mask. Then, an etching process is provided for etching the underlying layer using the photoresist pattern as an etching mask. The etching process may be carried out for manufacturing the semiconductor device. To form a pattern by selectively removing an object material in the etching process, various etching techniques have been developed and diverse etching equipments have been used.

The etching techniques may be classified into isotropic etching techniques and anisotropic etching techniques. The isotropic etching technique is one in which a layer is etched in a specific direction. Basically, it is an etching technique using a chemical reaction to implement the isotropic etching technique. A wet etching technique and a plasma etching technique can be employed to implement the isotropic etching technique. The anisotropic etching technique can use a reactive ion etching (RIE) technique. In the RIE process, reaction gases are ionized in a processing chamber. The ionized gases are electrically accelerated so that a specified layer is generally etched in the direction of a specified electric field. Plasma for activating the reaction gases is used in a dry etching technique. A high-frequency electric field is applied to the reaction gases to form the plasma.

In particular, a voltage is applied between upper and lower electrodes disposed in a plasma chamber to form an electric field therein. A reaction gas is supplied to a space between the upper and lower electrodes under a low pressure. The voltage may be generated using an alternating current, such as a high-frequency alternating current, or a direct current. When the direct current is used, the flow of the direct current may be cut off so that an insulation material for covering the electrodes is not used. When an alternating current is used, it is not necessary that both ends of the electrodes include a conductive material. Sufficient energy is provided to electrons between the upper and lower electrodes by vibration of the electric field so that the electrons collide against neutral atoms to create charged particles. The electrons generated in the space between the upper and lower electrodes collide against the neutral atoms to generate decomposition and luminescence, thereby creating more ions and electrons. Positive ions are accelerated by the electric field to collide against the electrodes, thereby creating additional electrons.

Meanwhile, when the charged particles are increased, the charged particles having different polarities collide with each other so that the total number of charged particles is decreased. When numbers of the charged particles generated in the etching process are balanced with numbers of the charged particles converted into the neutral particles, the plasma has a stable state. The stable plasma comprises partially ionized particles and neutral particles under a low pressure.

FIG. 1 is a cross sectional view illustrating a conventional plasma etching apparatus. Referring to FIG. 1, a conventional plasma etching apparatus includes an etching chamber 1 into which a reaction gas is introduced. An electrostatic chuck (ESC) 2 on which a wafer is disposed is mounted on a bottom face of the etching chamber 1. A lower electrode (not shown) is disposed under the ESC 2.

An upper electrode 3 for applying a high-frequency voltage to the reaction gas to form plasma is disposed at an upper portion of the etching chamber 1. A cooling plate 8 for cooling the upper electrode 3 is mounted on the upper electrode 3. A gas-diffusing ring 7 for providing the reaction gas into the etching chamber 1 is disposed beneath an edge of the upper electrode 3.

A matcher 6 for applying a radio frequency (RF) power to the upper electrode 3 is disposed over the etching chamber 1. The matcher 6 is disposed over the upper electrode 3. A vacuum pump 5 for providing vacuum into the etching chamber 1 is connected to a lower face of the etching chamber 1. A vacuum sensor 4 is attached to a sidewall of the etching chamber 1.

Since the wafer is heated at a high temperature in the etching process, controlling the temperature of the wafer by cooling is required. Thus, a temperature controller is provided to the ESC 2.

FIG. 2 is a perspective view illustrating a conventional temperature controller. Referring to FIG. 2, the conventional temperature controller includes a cooling line 10 formed in the ESC 2. The cooling line 10 has a spiral single line that extends from an edge portion of the ESC 2 to a central portion of the ESC 2 through the middle portion of the ESC 2. An edge portion of the cooling line 10, positioned at the edge portion of the ESC 2, corresponds to an inlet in which a refrigerant enters. A central portion of the cooling line 10, positioned at the central portion of the ESC 2, corresponds to an outlet from which the refrigerant exits.

A refrigerant bath 11 in which the refrigerant is contained is connected to the inlet of the cooling line 10. A valve 12 for controlling flux of the refrigerant is mounted on the inlet of the cooling line 10. A temperature sensor 13 for detecting a temperature of the refrigerant is mounted on the outlet of the cooling line 10.

The conventional temperature controller cools the wafer disposed on the ESC 2 using the refrigerant that flows through the single cooling line 10. Since the cooling line 10 is a single line, the conventional temperature controller may not separately control the central portion, the middle portion and the edge portion of the ESC 2. Particularly, the edge portion of the ESC 2, adjacent to the inlet of the cooling line 10, is cooled more rapid than the central portion of the ESC 2. As a result, the edge portion of the ESC 2 has a temperature below that of the central portion of the ESC 2. An etching rate is inversely proportional to the temperature so that the edge portion of the wafer has an etching rate greater than that of the central portion of the wafer. Accordingly, the wafer may not be etched uniformly.

To overcome the above problem, a conventional temperature controller illustrated in FIG. 3 is disclosed in Japan Laid Open publication No. 1993-243191.

Referring to FIG. 3, a conventional temperature controller includes first, second and third refrigerant baths 21, 22 and 23. A first cooling line 31 is connected between the first refrigerant bath 21 and an edge portion of an ESC 50. A second cooling line 32 is connected between the second refrigerant bath 22 and a middle portion of the ESC 50. A third cooling line 33 is connected between the third refrigerant bath 23 and a central portion of the ESC 50. First, second and third valves 41, 42 and 43 are mounted on inlets of the first, second and third cooling lines 31, 32 and 33, respectively. Also, first, second and third temperature sensors 61, 62 and 63 are installed at the first, second and third cooling lines 31, 32 and 33, respectively. First, second and third controllers 71, 72 and 73 control opening angles of the first, second and third valves 41, 42 and 43 in accordance with temperatures detected by the first, second and third temperature sensors 61, 62 and 63.

The conventional temperature controller separately provides different refrigerants from the first, second and third refrigerant baths 21, 22 and 23 to the edge portion, the middle portion and the central portion of the ESC 50 through the first, second and third cooling lines 31, 32 and 33, respectively. Thus, the conventional temperature controller may separately control the edge portion, the middle portion and the central portion of the ESC 50.

However, although the conventional temperature controller controls the temperature of the ESC by regions, one to one correspondence of the baths to the regions is required. When the numbers of the baths are increased, the temperature controller has complex structure and thus, high manufacturing cost of the temperature controller is resulted.

Also, the flux of the different refrigerants from the separate baths may not be readily controlled. Further, the separate baths may be independently managed.

SUMMARY OF THE INVENTION

The present invention provides a temperature controller capable of controlling temperatures of a stage by regions using one bath.

The present invention also provides an etching apparatus having the above-mentioned temperature controller.

A temperature controller system for controlling the temperature of an object in accordance with one aspect of the present invention includes a bath for containing a refrigerant. One cooling line has a first end connected to the bath and a second end opposite to the first end. The second end branches off into a plurality of diverged lines, e.g., first, second and third diverged lines. The first diverged line is connected to an edge portion of the object. The second diverged line is connected to a middle portion of the object. The third diverged line is connected to a central portion of the object. A plurality of valves for controlling a flux of the refrigerants are mounted on inlets of the plurality of diverged lines, respectively, through which the refrigerant flows to the object. A plurality of temperature sensors, e.g., first, second and third temperature sensors for detecting temperatures of the refrigerant are mounted on outlets of, e.g., the first, second and third diverged lines, respectively, through which the refrigerant flows from the object. A controller controls opening angles of the plurality of valves in accordance with the temperatures of the refrigerant detected by the first, second and third temperature sensors.

An apparatus in accordance with another aspect of the present invention includes an etching chamber into which a reaction gas for forming a plasma is introduced. An electrostatic chuck (ESC) on which a wafer is disposed is installed on a bottom face of the etching chamber. An upper electrode for applying a voltage to the reaction gas to form the plasma is disposed at an upper portion of the etching chamber. A cooling plate is mounted on the upper electrode. A temperature controller is connected to the ESC. The temperature controller includes a bath for containing a refrigerant. One cooling line has a first end connected to the bath and a second end opposite to the first end. The second end branches off into first, second and third diverged lines. The first diverged line is connected to an edge portion of the ESC. The second diverged line is connected to a middle portion of the ESC. The third diverged line is connected to a central portion of the ESC. First, second and third valves for controlling flux of the refrigerant are mounted on inlets of the first, second and third diverged lines, respectively, through which the refrigerant flows to the ESC. First, second and third temperature sensors for detecting temperatures of the refrigerant are mounted on outlets of the first, second and third diverged lines, respectively, through which the refrigerant flows from the ESC. A controller controls opening angles of the first, second and third valves in accordance with the temperatures of the refrigerant detected by the first, second and third temperature sensors.

An apparatus in accordance with still another aspect of the present invention includes an etching chamber into which a reaction gas for forming a plasma is introduced. An ESC on which a wafer is disposed is installed on a bottom face of the etching chamber. An upper electrode for applying a voltage to the reaction gas to form the plasma is disposed at an upper portion of the etching chamber. A cooling plate is mounted on the upper electrode. A temperature controller is connected to the cooling plate. The temperature controller includes a bath for containing a refrigerant. One cooling line has a first end connected to the bath and a second end opposite to the first end. The second end branches off into first, second and third diverged lines. The first diverged line is connected to an edge portion of the cooling plate. The second diverged line is connected to a middle portion of the cooling plate. The third diverged line is connected to a central portion of the cooling plate. First, second and third valves for controlling flux of the refrigerants are mounted on inlets of the first, second and third diverged lines, respectively, through which the refrigerant flows to the cooling plate. First, second and third temperature sensors for detecting temperatures of the refrigerants are mounted on outlets of the first, second and third diverged lines, respectively, through which the refrigerant flows from the cooling plate. A controller controls opening angles of the first, second and third valves in accordance with the temperatures of the refrigerant detected by the first, second and third temperature sensors.

An apparatus in accordance with still another aspect of the present invention includes an etching chamber into which a reaction gas for forming a plasma is introduced. An ESC on which a wafer is disposed is installed on a bottom face of the etching chamber. A first temperature controller is connected to the ESC. An upper electrode for applying a voltage to the reaction gas to form a plasma is disposed at an upper portion of the etching chamber. A cooling plate is mounted on the upper electrode. A second temperature controller is connected to the cooling plate. Each of the first and second temperature controllers includes a bath in which a refrigerant is contained. One cooling line has a first end connected to the bath and a second end opposite to the first end. The second end branches off into each of first, second and third diverged lines. Each of the first diverged lines is connected to an edge portion of the ESC and the cooling plate. Each of the second diverged lines is connected to a middle portion of the ESC and the cooling plate. Each of the third diverged lines is connected to a central portion of the ESC and the cooling plate. First, second and third valves for controlling flux of the refrigerant are mounted on inlets of the first, second and third diverged lines, respectively, through which the refrigerant flows to the ESC or the cooling plate. First, second and third temperature sensors for detecting temperatures of the refrigerants are mounted on outlets of the first, second and third diverged lines, respectively, through which the refrigerant flows from the ESC or the cooling plate. A controller controls opening angles of the first, second and third valves in accordance with the temperatures of the refrigerant detected by the first, second and third temperature sensors.

According to embodiments of the present invention, the temperatures of the object by regions may be readily controlled using one bath. Thus, the temperature controller has simple structure, and manufacturing cost of the temperature controller is decreased. Also, the flux of the refrigerants from one bath may be readily controlled.

BRIEF DESCRIPTION OF THE DRAWINGS

The above objects and advantages of the present invention will become more apparent by describing preferred embodiments in detail with reference to the attached drawings in which:

FIG. 1 is a cross sectional view illustrating a conventional etching apparatus;

FIG. 2 is a perspective view illustrating a conventional temperature controller;

FIG. 3 is a partially cross sectional view illustrating an etching apparatus having a conventional temperature controller;

FIG. 4 is a cross sectional view illustrating a temperature controller in accordance with a first embodiment of the present invention;

FIG. 5 is a cross sectional view illustrating an ESC in which the temperature controller in FIG. 4 is employed;

FIG. 6 is a cross sectional view illustrating an etching apparatus in accordance with a second embodiment of the present invention;

FIG. 7 is a cross sectional view illustrating an etching apparatus in accordance with a third embodiment of the present invention; and

FIG. 8 is a cross sectional view illustrating an etching apparatus in accordance with a fourth embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown.

Embodiment 1

Referring to FIG. 4, a temperature controller system 100 in accordance with the present embodiment of the present invention includes only one refrigerant bath 110 for containing a refrigerant. One cooling line 120 has a first end and a second end. The first end of the cooling line 120 is connected to the refrigerant bath 110. The second end of the cooling line 120 branches off into first, second and third diverged lines 131, 132 and 133.

The first diverged line 131 is connected to an edge portion of an object 240, for example an electrostatic chuck on which a wafer is disposed. The second diverged line 132 is connected to a middle portion of the object 240. The third diverged line 133 is connected to a central portion of the object 240.

Referring to FIG. 5, the first, second and third diverged lines 131, 132 and 133 are arrayed in concentric circles on the object 240. In particular, the first diverged line 131 formed on the edge portion of the object 240 has a circular shape having a first diameter. The second diverged line 132 formed on the middle portion of the object 240 has a circular shape having a second diameter less than the first diameter. The third diverged line 133 formed on the central portion of the object 240 has a circular shape having a third diameter less than the second diameter. Alternatively, the first, second and third diverged lines 131, 132 and 133 may be arrayed in spiral shapes. Also, the first, second and third diverged lines 131, 131 and 133 may have rectangular or triangular shapes.

Referring again to FIG. 4, first, second and third valves 141, 142 and 143 are mounted on inlets of the first, second and third diverged lines 131, 132 and 133, respectively, through which the refrigerant flows to the object 240. Particularly, the first valve 141 is mounted on the inlet of the first diverged line 131. The second valve 142 is mounted on the inlet of the second diverged line 132. The third valve is mounted on the inlet of the third diverged line 133.

According to the present embodiment, although the temperature controller system 100 has one refrigerant bath 110, the first, second and third valves 141, 142 and 143 separately control flux of the refrigerants flowing through the respective first, second and third diverged lines 131, 132 and 133.

The first, second and third diverged lines 131, 132 and 133 have outlets, respectively, through which the refrigerants flow from the object 240. First, second and third temperature sensors 151, 152 and 153 are installed on the outlets of the first, second and third diverged lines 131, 132 and 133, respectively.

A controller 160 controls the opening angles of the first, second and third valves 141, 142 and 143 in accordance with the temperatures of the refrigerants detected by the first, second and third temperature sensors 151, 152 and 153.

The refrigerants flow from the refrigerant bath 110 into the first, second and third diverged lines 131, 132 and 133 through the cooling line 120. Here, the first, second and the third valves 141, 142 and 143 separately control the flux of the refrigerants flowing through the first, second and third diverged lines 131, 132 and 133, respectively. Also, the first, second and third temperature sensors 151, 152 and 153 detect the temperatures of the refrigerants that exit from the respective first, second and third diverged lines 131, 132 and 133.

The temperatures of the refrigerants are transmitted to the controller 160. The controller 160 properly adjusts the opening angles of the first, second and third valves 141, 142 and 143 to uniformly cool the object 240.

For example, when a central temperature of the object 240 is higher than an edge temperature of the object 240, the controller 160 controls the third valve 143 to open wider than the first valve 141, thereby increasing the flux of the refrigerant flowing through the third diverged line 133 so that it is greater than that of the refrigerant flowing through the first diverged line 131. As a result, the object 240 can be substantially uniformly cooled.

Embodiment 2

Referring to FIG. 6, an etching apparatus 200 in accordance with the present embodiment of the present invention includes the temperature controller system 100 which is disposed in accordance with the first embodiment. Accordingly, identical reference numerals refer to substantially identical elements and a further illustration of the temperature controller system 100 is omitted.

The etching apparatus 200 includes an etching chamber 210 into which a reaction gas for forming a plasma is introduced. An electrostatic chuck 240 on which a wafer W is disposed is mounted on a bottom face of the etching chamber 210. A lower electrode (not shown) is disposed under the electrostatic chuck 240. The temperature controller system 100 is connected to the electrostatic chuck 240.

An upper electrode 220 for applying a high voltage to the reaction gas to form the plasma is disposed at an upper portion of the etching chamber 210. A cooling plate 230 for cooling the upper electrode 220 is mounted on the upper electrode 220. A gas-diffusing ring 270 for uniformly diffusing the reaction gas into the etching chamber 210 is disposed beneath an edge of the upper electrode 220.

An RF matcher 260 for applying an RF power to the upper electrode 220 is disposed over the upper electrode 210. A vacuum pump 250 for providing vacuum into the etching chamber 210 is connected to a lower portion of the etching chamber 210. A vacuum sensor 280 is attached to a sidewall of the etching chamber 210.

Embodiment 3

Referring to FIG. 7, an etching apparatus 200 in accordance with the present embodiment of the present invention includes the temperature controller system 100 designed in accordance with the first embodiment. Accordingly, identical reference numerals refer to substantially identical elements and a further illustration of the temperature controller system 100 is omitted.

The etching apparatus 300 includes an etching chamber 310 into which a reaction gas for forming a plasma is introduced. An electrostatic chuck 340 on which a wafer W is disposed is mounted is disposed on the bottom face of the etching chamber 310. A lower electrode (not shown) is disposed under the electrostatic chuck 340.

An upper electrode 320 for applying a high voltage to the reaction gas to form the plasma is disposed at an upper portion of the etching chamber 310. A cooling plate 330 for cooling the upper electrode 320 is mounted on the upper electrode 320. The temperature controller system 100 is connected to the cooling plate 330.

A gas-diffusing ring 370 for uniformly diffusing the reaction gas into the etching chamber 310 is disposed beneath an edge of the upper electrode 320. An RF matcher 360 for applying an RF power to the upper electrode 320 is disposed over the upper electrode 310. A vacuum pump 350 for providing vacuum into the etching chamber 310 is connected to a lower portion of the etching chamber 310. A vacuum sensor 380 is attached to a sidewall of the etching chamber 310.

Embodiment 4

Referring to FIG. 8, an etching apparatus 400 in accordance with the present embodiment of the present invention includes an etching chamber 410 into which a reaction gas for forming a plasma is introduced. An electrostatic chuck 440 on which a wafer W is disposed is mounted on a bottom face of the etching chamber 410. A lower electrode (not shown) is disposed under the electrostatic chuck 440. A first temperature controller system 100 a is connected to the electrostatic chuck 440. Here, the first temperature controller system 100 a has elements substantially identical to those of the temperature controller system 100 in accordance with the first embodiment. Thus, an illustration of the first temperature controller system 100 a is omitted.

An upper electrode 420 for applying a high voltage to the reaction gas to form the plasma is disposed at an upper portion of the etching chamber 410. A cooling plate 430 for cooling the upper electrode 420 is mounted on the upper electrode 420. A second temperature controller system 100 b is connected to the cooling plate 430. Here, the second temperature controller system 100 b also has elements substantially identical to those of the temperature controller system 100 in accordance with the first embodiment. Thus, an illustration of the second temperature controller system 100 b is omitted.

A gas-diffusing ring 470 for uniformly diffusing the reaction gas into the etching chamber 410 is disposed beneath an edge of the upper electrode 420. An RF matcher 460 for applying an RF power to the upper electrode 420 is disposed over the upper electrode 410. A vacuum pump 450 for providing vacuum into the etching chamber 410 is connected to a lower portion of the etching chamber 410. A vacuum sensor 480 is attached to a sidewall of the etching chamber 410.

According to the present invention, the valves may be mounted on the diverged lines from one refrigerant bath so that the temperatures of the object by regions may be readily controlled using the temperature controller system that has only one bath as previously described. Thus, the temperature controller system has simple structure, and the manufacturing cost of the temperature controller system can be decreased.

Also, the etching apparatus having the temperature controller system may etch the wafer by a uniform thickness.

Having described the preferred embodiments of the present invention, it is noted that modifications and variations can be made by persons skilled in the art in light of the above teachings. It is therefore to be understood that changes may be made in the particular embodiment of the present invention disclosed which is within the scope and the spirit of the invention outlined by the appended claims. 

1. A temperature controller system for controlling the temperature of an object, the system comprising: a refrigerant bath for containing a refrigerant; a cooling line having a first end connected to the refrigerant bath and a second end opposite to the first end; a plurality of diverged lines connected at one end to the second end of the cooling line, and connected at the other end to the object; a plurality of valves respectively mounted on the plurality of diverged lines; a plurality of sensors for detecting temperatures of the refrigerant flowing through the plurality of diverged lines; and a controller for controlling opening angles of the valves in accordance with the temperatures of the refrigerant detected by the plurality of temperature sensors.
 2. The temperature controller system of claim 1, wherein a first diverged line is connected to an edge portion of the object, a second diverged line is connected to a middle portion of the object, and a third diverged line is connected to a central portion of the object.
 3. The temperature controller system of claim 2, wherein the first, second and third diverged lines are formed in concentric circles on the object.
 4. The temperature controller system of claim 1, wherein the plurality of valves are respectively mounted on inlets of the plurality of diverged lines through which the refrigerant flows into the object.
 5. The temperature controller system of claim 1, wherein the sensors are mounted respectively on outlets of the plurality of diverged lines, through which the refrigerant flows from the object.
 6. An etching apparatus comprising: an etching chamber for introducing a reaction gas for forming a plasma therein; an electrostatic chuck disposed on a bottom face of the etching chamber for supporting a wafer thereon; and a temperature controller system including a refrigerant bath for containing a refrigerant, a cooling line having a fist end connected to the refrigerant bath and a second end opposite to the first end, a plurality of diverged lines connected at one end to the second end of the cooling line and connected at the other end to the electrostatic chuck, a plurality of valves respectively mounted on the plurality of diverged lines, a plurality of sensors for detecting temperatures of the refrigerant flowing through the plurality of diverged lines, and a controller for controlling opening angles of the valves in accordance with the temperatures of the refrigerant detected by the plurality of temperature sensors.
 7. The etching apparatus of claim 6, wherein a first diverged line is connected to an edge portion of the electrostatic chuck, a second diverged line is connected to a middle portion of the electrostatic chuck, and a third diverged line is connected to a central portion of the electrostatic chuck.
 8. The etching apparatus of claim 7, wherein the diverged lines are formed in concentric circles on the electrostatic chuck.
 9. The etching apparatus of claim 6, wherein the plurality of valves are respectively mounted on inlets of the plurality of diverged lines.
 10. The etching apparatus of claim 6, wherein the sensors are respectively mounted on outlets of the plurality of diverged lines.
 11. An etching apparatus comprising: an etching chamber for introducing a reaction gas for forming a plasma threin; an electrostatic chuck disposed on a bottom face of the etching chamber for supporting a wafer thereon; an upper electrode disposed at an upper portion of the etching chamber, the upper electrode for applying a voltage to the reaction gas to form the plasma; a cooling plate for cooling the upper electrode; and a temperature controller system including a refrigerant bath for containing a refrigerant, a cooling line having a fist end connected to the refrigerant bath and a second end opposite to the first end, a plurality of diverged lines connected at one end to the second end of the cooling line and connected at the other end to the electrostatic chuck, a plurality of valves respectively mounted on the plurality of diverged lines, a plurality of sensors for detecting temperatures of the refrigerant flowing through the plurality of diverged lines, and a controller for controlling opening angles of the plurality of valves in accordance with the temperatures of the refrigerant detected by the plurality of temperature sensors.
 12. The etching apparatus of claim 11, wherein a first diverged line is connected to an edge portion of the cooling plate, a second diverged line is connected to a middle portion of the cooling plate, and a third diverged line is connected to a central portion of the cooling plate.
 13. The etching apparatus of claim 12, wherein the first, second and third diverged lines are formed in concentric circles on the cooling plate.
 14. The etching apparatus of claim 1 1, wherein the plurality of valves are respectively mounted on inlets of the plurality of diverged lines, through which the refrigerant flows into the electrostatic chuck.
 15. The etching apparatus of claim 11, wherein the sensors are respectively mounted on outlets of the plurality of diverged lines, through which the refrigerant flows from the object.
 16. An etching apparatus comprising: an etching chamber for introducing a reaction gas for forming a plasma therein; an electrostatic chuck disposed on a bottom face of the etching chamber, the chuck for supporting a wafer thereon; a first temperature controller system for controlling a temperature of the electrostatic chuck; an upper electrode disposed at an upper portion of the etching chamber, the upper electrode for applying a voltage to the reaction gas to form the plasma; a cooling plate for cooling the upper electrode; and a second temperature controller system for controlling a temperature of the cooling plate, a temperature controller system including a refrigerant bath for containing a refrigerant, a cooling line having a fist end connected to the refrigerant bath and a second end opposite to the first end, a plurality of diverged lines connected at one end to the second end of the cooling line and connected at the other end to the electrostatic chuck, a plurality of valves respectively mounted on the plurality of diverged lines, a plurality of sensors for detecting temperatures of the refrigerant flowing through the plurality of diverged lines, and a controller for controlling opening angles of the plurality of valves in accordance with the temperatures of the refrigerant detected by the plurality of temperature sensors.
 17. The etching apparatus of claim 16, wherein at least one first diverged line is connected to an edge portion of the electrostatic chuck and the cooling plate, respectively, at least one second diverged line is connected to a middle portion of the electrostatic chuck and the cooling plate, respectively, and at least one third diverged line is connected to a central portion of the electrostatic chuck and the cooling plate, respectively.
 18. The etching apparatus of claim 17, wherein the first, second and third diverged lines are formed in concentric circles on the electrostatic chuck and the cooling plate.
 19. The etching apparatus of claim 16, wherein the plurality of valves are respectively mounted on inlets of the plurality of diverged lines, through which the refrigerant flows into the electrostatic chuck.
 20. The etching apparatus of claim 16, wherein the sensors are respectively mounted on outlets of the plurality of diverged lines, through which the refrigerant flows from the object. 